I regularly check yallo.ch for new postpaid offers and found out that they give out free prepaid SIM with 5 SFR credit on it.
I ordered one to use as my second SIM in my workphone just to collect data for this project.
So I have the following setup:
- Nokia 6.1 with Swisscom SIM and Sunrise (Yallo) SIM
- Nokia 7.1 with Salt SIM.
With this setup I am able to scan all three networks in Switzerland.